Hyperimmune Colostrum-Influenza Antibody

Abstract Background:

Despite the availability of specific vaccines and antiviral drugs, influenza continues to impose a heavy toll on human health worldwide. Passive transfer of specific antibody (Ab) may provide a useful means of preventing or treating disease in unvaccinated individuals or those failing to adequately seroconvert, especially now that resistance to antiviral drugs is on the rise.

However, preparation of appropriate Ab in large scale, quickly and on a yearly basis is viewed as a significant logistical hurdle for this approach to control seasonal influenza. Methodology/Principal Findings: In this study, bovine colostrum, which contains approximately 500 g of IgG per milking per animal, has been investigated as a source of polyclonal antibody for delivery to the respiratory tract. IgG and F(ab’)2 were purified from the hyperimmune colostrum of cows vaccinated with influenza A/Puerto Rico/8/34 (PR8) vaccine and were shown to have high hemagglutination-inhibitory and virus-neutralizing titers. In BALB/c mice, a single administration of either IgG or F(ab’)2 could prevent the establishment of infection with a sublethal dose of PR8 virus when given as early as 7 days prior to exposure to virus. Pre-treated mice also survived an otherwise lethal dose of virus, the IgG- but not the F(ab’)2-treated mice showing no weight loss. Successful reduction of established infection with this highly virulent virus was also observed with a single treatment 24 hr after virus exposure. Conclusions/Significance: These data suggest that a novel and commercially-scalable technique for preparing Ab from hyperimmune bovine colostrum could allow production of a valuable substitute for antiviral drugs to control influenza with the advantage of eliminating the need for daily administration.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The study was funded by grants from the National Health and Medical Research Council of Australia and the Australian Research Council (Linkage project LP0990420), who had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript, and by Immuron Limited who had no role in data collection and analysis and decision to publish but provided input into study design and manuscript preparation. Competing Interests: GR, BM and VW are employees of Immuron Limited (www.immuron.com), who hold the patents for this technology. WCN was partially funded by Immuron Ltd. This does not alter the authors’ adherence to all the PLoS ONE policies on sharing data and materials.